Support switching between personal and work profiles in Codex

What version of the Codex App are you using (From "About Codex" dialog)?

_No response_

What subscription do you have?

_No response_

What platform is your computer?

_No response_

What issue are you seeing?

A profile switcher in Codex would be useful for users who need to separate personal and work usage.

Requested workflow: use a personal account/profile for personal projects, and a work account/profile for work-related tasks, without manually signing out or mixing account state across projects.

Related existing issues:

• #4432
• #12029
• #14330
• #18806

What steps can reproduce the bug?

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What is the expected behavior?

Codex should support switching between named profiles/accounts, so users can choose the right personal or work identity for each project/task.

Additional information

_No response_